Gregory W. Gladish MD, Presenter: Nothing to Disclose

Dianna Cody PhD, Abstract Co-Author: Nothing to Disclose

Dawn Cavanaugh, Abstract Co-Author: Nothing to Disclose

Roger Eugene Price DVM, PhD, Abstract Co-Author: Nothing to Disclose

Belinda Rivera BS, Abstract Co-Author: Nothing to Disclose

Reginald Frank Munden DMD, Abstract Co-Author: Nothing to Disclose

To evaluate new CT technology with potentially improved spatial resolution on the thorax of a non-human subject in-vivo.

A dual-panel CT scanner with a maximum display field of view of 32 cm was used to examine the thorax of a 20 kg dog intubated and anesthetized with isoflurane inhalation anesthesia. Scan parameters were 120 kV, 100 mA, 2 sec per rotation, 500 views per rotation, 3.4 cm coverage (z-direction) per rotation, and five rotations. Total scan time was 18 seconds. During the imaging a breath-hold was initiated and maintained by a veterinary technician manually compressing the bag of a non-rebreathing inhalation anesthesia system after manually hyperventilating the dog for several seconds. Image reconstructions were generated with voxels that were initially 0.5 mm (isotropic) and the display field of view was 24 cm. Targeted reconstructions (zoomed views) were generated with 0.325 mm isotropic voxels and 0.150 mm isotropic voxels.

Sixth to tenth order bronchial tree branches and seventh to ninth order vasculature tree branches were visible in the resulting images. Using the image set consisting of the smallest voxels (near the limiting resolution of this scanner), pulmonary vessels that were 0.3 mm in diameter were apparent. Bronchial wall thickness was also measurable down to 0.3 mm in dimension. The multiplanar reformats revealed detail that was identical to that of the axial images, as expected. Image processing and review tools able to handle and display large data sets will be a necessary requirement for full-scale implementation of this technology. Overall, impressive detail was noted during image review, even though some artifacts and respiratory motion somewhat degraded the image quality.

Initial experience with digital flat panel CT shows a potential for increased spatial resolution relative to conventional CT and for imaging of small airway anatomy. Further evaluation of this technology and its application to pulmonary imaging should be performed.

Gladish, G, Cody, D, Cavanaugh, D, Price, R, Rivera, B, Munden, R, Preliminary in-Vivo Results from an Experimental Flat-panel CT System.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4403606.html